We report herein the results of operatively treating 44 consecutive acute fractures of the humeral shaft using plates for internal fixation. Ninety-seven percent (43 of 44) of the fractures healed after plate fixation at an average of 12 weeks. One short plate pulled out and required revision with a longer plate and bone grafting; this fracture also healed. Cancellous bone grafting successfully filled in cortical bone gaps. Range of motion of the shoulder and elbow were essentially normal. Plate size varied depending on the location of the fracture and bone size. Eight of nine fractures treated with 3.5-mm compression plates healed uneventfully. All 11 open fractures, eight from bullet wounds, healed uneventfully after early plating. Fifteen radial nerve injuries were associated with the fractures. Twelve anatomically intact radial nerve palsies recovered in 17 weeks on average after plate fixation. One lacerated nerve was sutured and recovered. One nerve with segmental loss associated with an open fracture was left unrepaired, as was an avulsed nerve associated with a closed fracture. The dissection required for plate fixation provides information that may be helpful in determining appropriate treatment of radial nerve injuries and the prognosis for spontaneous return of function.